(adsbygoogle = window.adsbygoogle || []).push({}); PLEASE help!!! Kepler's third law for electrical orbits

Hi there! I hope someone can help me with this problem. I've been working on this for over 5 hours and I've gotten nowhere!

A positron is a particle with the same mass as an electron but with a positive charge. A positron and an electron can briefly form an unusual atom known as positronium. Imagine a situation where the two particles are in a circular orbit about their center of mass. Since the particles have equal mass, the center of mass is midway between them. Let r be the separation of the particles (so that the orbits are each of radius r/2).

(a) Show that the orbital period T is related to the separation distance r by:

T^2 = (16)(pi^3)(E0)(me)(mp) (r^3)

---------------------

(e^2)[(me) + (mp)]

This is a consequence of Kepler's third law for electrical orbits.

(b) Show that if an electron and aprotonare in circular orbits about their center of mass (which is not at the midway point between them but much closer to the proton), then the same expression results.

* * * * *

OK, so so far, I'm guessing that I somehow use the formulae:

q = ne

F = 1 |Q||q|

-------- x ---------

4(pi)(E0) (r^2)

But I'm not really sure where the rest of it comes from

If someone could help me out, I would really appreciate it!

Thanks!

Mandy

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# Homework Help: PLEASE help Kepler's third law for electrical orbits

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